Abstract
Chicken droppings are commonly applied prior to wheat sowing in autumn in the wheat-paddy rice double cropping system. It is used as organic fertilizer instead of customary chemical fertilizer. We investigated the effects of the chicken droppings on yields of wheat and rice and on the contents of nitrogen, phosphoric acid and potassium in soil. Wheat yields with chicken dropping was higher than with no chicken droppings: The spike numbers, kernels per spike and thousand kernels weight were all higher with chicken droppings. However, the wheat yield was lower with chicken droppings than with customary chemical fertilizer. Rice yields with chicken droppings was not different from that without chicken droppings but was lower than with customary chemical fertilizer. After wheat harvest, the nitrogen content of soil before and after succeeding rice cultivation was nearly the same in the fields with and without chicken droppings. On the other hand, phosphoric acid and potassium contents of soil were lower after rice cultivation than before rice cultivation. Chicken dropping were effective as nitrogen fertilizer for wheat immediately after spraying but not for succeeding rice in the wheat-paddy rice double cropping system. On the other hand, chicken droppings were effective as phosphoric acid and potassium fertilizer for both wheat and rice cultivation.
